The present invention relates to a new catheter assembly, a catheter stabilizing device and a device for removing a catheter assembly having a catheter stabilizing device.
Catheters, shunts, drainage tubes and the like, generally referred to herein as catheters, may be located in various locations within the human body for the introduction and removal of fluid from the body. Once in place, such catheters are typically anchored by a stabilizing device or sutured in place. Stabilizing devices generally are provided in several different types. Many catheters include a winged collar or cuff having suture holes formed in an outer area of the device. The collar or cuff freely rotates about the catheter. Catheters may also be taped to a patient""s skin, however, taping alone is generally not sufficiently reliable to stabilize the device.
Another common catheter stabilizing device is a tissue-ingrowth cuff. Such a cuff is typically made of Dacron(copyright) or a similar biocompatible material, and is attached by an adhesive layer to the outer surface of a catheter cannula. The cuff is generally located on the catheter such that when a distal portion of the catheter is in position in a location to be catheterized, the cuff is positioned external to the catheterized part of the body, but below the surface of the skin in subcutaneous tissue.
In some cases, the cuff is positioned on the catheter such that when the distal portion of the catheter is inserted in the body part, the cuff is located in a subcutaneous tunnel. The tunnel is formed by a tunnelling tool, such as a trocar, either before or after cannulation of the vessel with the distal portion of the catheter. The proximal portion of the catheter having the cuff is drawn through the tunnel by the tool while the tool passes through the subcutaneous tissue. The cuff is generally sized such that when the procedure is done, the cuff will fit snugly in the tunnel or other area.
After a period of time, the surrounding tissue grows into the fabric of the cuff such that the catheter is stabilized in the catheterized location. In addition, the catheterized location and the subcutaneous tunnel are sealed off, preventing foreign bodies from entering the wound and blood from exiting or pooling around the catheter near the exit site, thereby preventing patient infection. While such fabric cuffs are inexpensive to make and are generally effective at stabilizing a catheter, they are also difficult to remove.
In order to remove such a cuff from ingrown subcutaneous tissue, such as a tunnel, a physician has to detach the cuff by cutting around the cuff with a scalpel. The physician has to cut the subcutaneous tissue surrounding all edges of the cuff into which tissue has grown. Tissue growth occurs substantially transverse to the longitudinal axis of the cuff around the outer circumference of the cuff. In addition, tissue growth occurs at angles oblique to the longitudinal axis of the cuff along both of the cuff""s side edges. The physician must cut around the circumference of the cuff and both side edges to detach the cuff in a difficult, time-consuming surgical procedure that can increase patient bleeding. Such prolonged surgery and increased bleeding presents several risks to both the physician and patient, including the increased risk of infection. The procedure may also possibly contribute to an increased chance of scar tissue build-up within the subcutaneous area such that patients requiring multiple catheterization procedures may become increasingly difficult to catheterize.
The fabric cuffs also pose problems in the subcutaneous tunnelling procedures. Because the cuffs are sized to provide a snug fit in the subcutaneous area, they are difficult to pull smoothly through the tunnel. With catheters formed of softer durometer materials, such as pellethane and silicone, for example, the cuffs increase the risk that the catheter will snap or break apart during the tunnelling or removal procedure, and tend to elongate the tube and alter its dimensions. The stress placed on the proximal end of the catheter during the tunnelling procedure or during removal to pull the catheter through the tunnel is concentrated at the location of the cuff. As the cuff fits snugly within the subcutaneous tunnel, frictional forces against the tunnel wall affect the tunnelling and removal of the catheter. If the catheter breaks during removal, the physician may have to perform a further procedure to remove the broken-off distal portion of the catheter left within the patient. If the catheter breaks during the initial tunnelling procedure, the physician may have to completely recatheterize the patient.
Based on the foregoing disadvantages of prior art catheter stabilizing devices, particularly fabric cuffs, there is a need in the art for a stabilizing device which prevents the pooling of blood and invasion of foreign bodies by sealing a catheterized location, but which does not tend to break during placement or removal and which is easily removable without prolonged or invasive surgical cutting of subcutaneous tissue. There is also a need in the art for a device for safely removing such a stabilizing device from a subcutaneous location without the need for surgical cutting of the subcutaneous tissue.
The catheter stabilizing cuff of the present invention provides structural reinforcement to a catheter such that the catheter does not tend to break during catheterization or removal. It is easily removable without prolonged or invasive surgical cutting of subcutaneous tissue. Further, it can be removed without any surgical cutting when using the device for removing a catheter assembly of the present invention.
The present invention includes a composite catheter stabilizing device which includes a cuff and a first and second end piece. The cuff has a first edge and a second edge, and is configured for positioning around a catheter. The device also includes a first end piece and a second end piece. The first and second end pieces have internal surfaces which define tubular openings that extend through the end pieces. The first end and second end pieces is have external surfaces which are tapered from their first sides to their second sides. The first sides of the first and second end pieces abut the first and second edges of the cuff, respectively. The second sides of the first and second end pieces are configured for receiving a catheter in facing engagement.
The invention also includes a catheter assembly which includes a catheter and a catheter stabilizing device. The catheter has an external surface and at least one lumen which extends through the catheter. The stabilizing device includes a cuff, a first end piece and a second piece. The cuff has a first edge and a second edge, and is adhered to the external surface of the catheter. The first and second end pieces have external surfaces and internal surfaces which are configured to conform to the external surface of the catheter in facing engagement. The external surfaces of the first and second end pieces are tapered from the first sides of the first and second end pieces, which respectively abut the first and second edges of the cuff, to the second sides of the first and second end pieces.
The invention also includes a method for making a catheter assembly having a composite catheter stabilizing device. A cuff having a first edge and a second edge is affixed to the external surface of a catheter. A first end piece having an internal surface, a first side and a second side is positioned around the external surface of the catheter such that the first side abuts the first edge of the cuff. A second end piece having an internal surface, a first side and a second side is positioned around the external surface of the catheter such that the first side abuts the second edge of the cuff. The first and second end pieces are tapered from their first sides to their second sides. The first and second end pieces are affixed to the external surface of the catheter such that the second sides of the end pieces are in facing engagement with the external surface of the catheter.
In an alternative embodiment, the method includes forming a unitary catheter which has an external surface, a lumen extending through the catheter, and a first and a second end piece. The first and second end pieces are tapered from the external surface of the catheter to first sides which lie in a plane perpendicular to the longitudinal axis of the catheter. The first sides of the first and second end pieces are facing and spaced from each other. A cuff having a first edge and a second edge is affixed to the external surface of the catheter between the first and second end pieces such that the first edge of the cuff abuts the first side of the first end piece and the second edge of the cuff abuts the first side of the second end piece. The end pieces and the cuff form the composite catheter stabilizing device.
An alternative embodiment of a composite catheter stabilizing device is included in the invention which includes a unitary base and a cuff. The base has an internal surface which defines a tubular opening that extends through the base and that has a first end piece, a second end piece, and an annular central portion positioned between the first and second end pieces. The first end piece has an external surface tapered from a first side toward a second side, the second end piece has an external surface tapered from a first side to a second side and the internal surface is configured for positioning around a catheter. The cuff has a first edge that abuts the first side of the first end piece and a second edge that abuts the first side of the second end piece. The cuff is configured for positioning around the central portion of the base.
An alternative method is also provided for making a catheter assembly having a composite catheter stabilizing device. The method includes affixing a base to the external surface of the catheter. The base has an internal surface which defines a tubular opening and has a first end piece, a second end piece and a central portion. The base is affixed to the catheter such that the internal surface of the base is in facing engagement with the external surface of the catheter. The external surfaces of the first and second end pieces are each tapered from a first side to a second side. A cuff is affixed to the external surface of the central portion of the base such that a first edge of the cuff abuts the first side of the first end piece and a second edge of the cuff abuts the first side of the second end piece.
A device for removing a catheter assembly having a catheter stabilizing device including a tissue ingrowth cuff from a subcutaneous location is also provided in the present invention. The device includes a handle and a head. The handle has a proximal end, and a distal end. The head is attached to the distal end of the handle, and has an external gripping surface. The head is sized for insertion into a lumen of a catheter assembly having a tissue ingrowth cuff for gripping an internal surface of the catheter assembly within the cuff and dislodging the cuff from surrounding tissue.
A method for removing a catheter assembly having a catheter stabilizing device including a tissue ingrowth cuff which is grown into a subcutaneous location is also included in the present invention. The catheter assembly is removed by a device having a handle and a head having an external gripping surface. The method includes inserting the head of the device into a proximal end of a lumen extending through the catheter assembly, inserting the head further into the lumen by pushing the handle of the device until a distal end of the head is substantially longitudinally aligned with a distal end of the tissue ingrowth cuff, and pulling the handle to dislodge the tissue ingrowth cuff and to remove the catheter assembly from the subcutaneous location.